1. Field of the Invention
The present invention relates to semiconductor devices, and more particularly to a process for fabricating a semiconductor device having a suspended micro-system, the resultant semiconductor device, and its applications.
2. Description of Related Art
Suspended micro-systems, which are also known as semiconductor suspended structures, in integrated circuits are generally used in the case in which there is the necessity to provide orthogonal movements of portions of the surface of a crystal of silicon opportunely worked. The use of such micro-systems can be, for example, for the realization of a thermally moved micro-mirror.
The obtainment of such structures is a very complex process. The complexity is to be found in the impossibility of realizing sacrificial layers of elevated thickness, for example of about ten microns, with the VLSI and ULSI technologies.
Traditionally this drawback is resolved through the use of processes that require the bulk working (i.e., from the back) of the silicon structure through anisotropic erosion activated by basic solutions such as KOH or TMAH, or through techniques of wafer bonding or smart cutting, or by using silicon wafer on insulator technology.